Studies of the toxicity of Helminthosporium maydis.

Isolates of Helminthosporium maydis from blighted corn were tested for toxicity in mice, rats, swine, rabbits, microorganisms, and tissue culture. Extracts of grains, mycelia, and culture supernatant fluids killed mice on intraperitoneal (ip) injection, but were nontoxic on administration by mouth to swine. The toxin was partially purified and appears to be a glycophospholipid. Histopathological examination revealed that the toxin acted as a severe irritant on ip injection, causing death in laboratory animals. In skin tests with rabbits, considerable exudation occurred, rather than necrosis.